@jzillw eh, I think the intent for the first mission is just "get comfortable with the driving mechanics, finding buildings, learning how to exit." When it starts being timed after that it really eases you into it a few minutes is more than enough time to loot most early areas, then by the time you get to mid areas you generally start each zone making a plan for your route. You also get infinite time on certain story missions later as well. There IS checkpointing just not within the current zone